There has been widespread speculation over the North Korean leader’s condition.

A top South Korean official has said his country remains confident that there have been no “unusual developments” in North Korea, suggesting that rumours about the health of leader Kim Jong Un are untrue.

Unification minister Kim Yeon-chul told a closed-door forum in Seoul on Sunday that South Korea has “enough intelligence to confidently say that there are no unusual developments” in North Korea which back up speculation about Kim Jong Un’s health.

The minister said he would not reveal what specific intelligence led to that conclusion, but stressed that it had undergone a complex analysis process.

Visitors look on the wire fence decorated with ribbons written with messages wishing for the reunification of the two Koreas at the Imjingak Pavilion in Paju (AP)

The rumours about Mr Kim’s health began to swirl after he missed the April 15 commemoration of the 108th birthday of his grandfather, North Korea’s founder Kim Il Sung.

Mr Kim is the third generation of his family to rule North Korea, and he had not missed the event, one of the most important in the North, since assuming power after his father Kim Jong Il’s death in late 2011.

North Korea’s state media has since made no mention of Mr Kim’s health or his public activities, though they said he had received some messages of greeting from foreign countries.

On Monday, North Korea’s state TV broadcast said Mr Kim sent his thanks to workers and officials at a tourist resort construction site on the east coast.

The unification minister’s comments are a reiteration of previous South Korean statements maintaining that Mr Kim appeared to be handling state affairs normally and that no unusual activities had been detected in the North.

Those earlier comments failed to dispel the rumours about Mr Kim, which have been fed by the silence of North Korea’s state media about their leader’s whereabouts.

As the absolute leader of country with a nuclear weapons programme, Mr Kim’s health is matter of intense interest both regionally and globally.

If something were to happen to Mr Kim, some experts have said it could lead to instability in North Korea.

South Korea’s presidential office earlier said it has information that Mr Kim has been staying out of Pyongyang and that there had been no emergency readiness order issued by the North’s military or the ruling Workers’ Party that likely would have been made if Mr Kim were truly in a bad condition.

On Monday, South Korean president Moon Jae-in repeated an offer to conduct some inter-Korean cooperation projects such as a joint anti-coronavirus quarantine campaign.

Mr Moon also said he will strive for mutual prosperity “based on confidence between Chairman Kim and me and our firm resolve to (achieve) peace”.

Monday is the second anniversary of Mr Moon’s first summit with Mr Kim at the Korean border village of Panmunjom.

Recent satellite photos released Saturday by 38 North, a website specialising in North Korea studies, showed that a train likely belonging to Mr Kim has been parked at his compound on the country’s east coast since last week.

The site said: “The train’s presence does not prove the whereabouts of the North Korean leader or indicate anything about his health, but it does lend weight to reports that Kim is staying at an elite area on the country’s eastern coast.”